Panasonic PT-DZ12000U Operating Instructions Manual page 151

How many square feet of solar panel do you need?
Example: From our previous example you need a minimum of
18,000 watt-hours per day from your solar panels. With 6
hours per day of available sunlight you need to collect 3,000
watts per hour. Your solar panels may have a capacity of 10
watts per square foot. Therefore you need 300 square feet of
solar panels for this example. My wife and I use 20,000 watt-
hours per day at our home and that is fairly typical for a small
home in northern New Mexico.
18,000 watt-hrs / 6 hours = 3,000 watts per hour
3,000 watts / 10 watts per square foot = 300 square feet
Refer to the National Renewable Energy Laboratory
website at WWW.NREL.GOV for a map depicting solar power
availability in the US.
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